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1.
荒漠沙蜥的年龄划分徐海根(国家环保局南京环境科学研究所,210042)杨凤翔,宋志明(兰州大学,730000)(四川大学,成都610064)AgeDifferentiationofPhrynocephalusprzewalskiionDescrts¥.XuHaigen(NanjingInstituteofEnuiron-mentalSciences,210042),YangFengxiang(LanzhouUniuersity,730000),SongZhiming(SichuanUniuer-sity,Chengdu610064).ChineseJournalofEcology,1993,12(4):30-32.Usingmark-recapturemethodandaccordingtothesnout-ventlengthgrowthpattern,fiveagegroupsofPhry,iocephalusprzewalskiiondesertsaredifferentiatecd.Andbasedonthedataoflizardsmorpholo-gy,thecommunityofPhrynoc  相似文献   

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油梨胚、胚乳发育的研究彭民璋邓九生谢荔元(广西农工商职业大学,南宁530227)StudiesontheDevelopmentofEmbryoandEndospermofAvocadoPengMing-zhangDengJiu-shengXieLi-...  相似文献   

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ExpressionofPorcineGrowthHormoneGeneinCHOCellCHENQing-xuan(陈清轩);HEXin(何新);DENGHui-nan(邓辉南)(InstituteofDevelopmentalBiology,Ac...  相似文献   

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酸雨和SO2暴露对一些不同抗性幼树的影响   总被引:10,自引:0,他引:10  
酸雨和SO2暴露对一些不同抗性幼树的影响陈树元徐和宝谢明云张福珠苗鸿张宏瑞(江苏省中国科学院植物研究所,南京210014)(中国科学院生态环境研究中心,北京100085)EfectsoftheAcidRainandSulfuricDioxideExp...  相似文献   

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黑线姬鼠肥满度的研究   总被引:10,自引:1,他引:9  
杨再学 《兽类学报》1995,15(1):73-74,24
黑线姬鼠肥满度的研究STUDYONTHERELATIVEFATNESSOFTHESTRIPEDFIELDMOUSE(APODEMUSAGRARIVS)KeywordsStripedfieldmouse(Apodemus:agrarius);Relat...  相似文献   

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应用生态学报第5卷(1994)关键词索引CHINESEJOURNALOFAPPLIEDECOLOGYVol.5(1994)KEYWORDINDEXAAcanthopanaxsenlicosusigloo5(3):237Agroecosystem¥k4...  相似文献   

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本工作对低频(2Hz)和高频(100Hz)电针引起大鼠中枢Fos/Jun表达和三类阿片肽基因表达进行了详细的比较研究,并用针对c-fos/c-jun的反义寡核苷酸(ODNs)对电针引起的Fos/Jun表达进行选择性阻断,然后观察阿片肽基因表达是否受到影响,以确定Fos/Jun复合物在电针引起阿片肽基因表达中的作用。主要结果如下:(1)2Hz和100Hz电针引起脑内不同部位的Fos/Jun表达;(2)2Hz电针使前脑啡肽原(PPE)mRNA表达大幅度增高,100Hz电针也能增加PPEmRNA的转录,但不如2Hz电针的作用显著;但100Hz电针能使某些脑区的前强啡肽原(PPD)基因转录加速,而2Hz电针没有这一作用;(3)用c-fos/c-jun反义ODNs特异地阻断Fos/Jun表达后,电针引起的PPD转录加速被明显阻断,而PPE表达不受影响。提示Fos/Jun是电针引起PPD(而非PPE)基因表达的转录因子。  相似文献   

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枯草芽孢杆菌中性内切β-甘露聚糖酶的纯化及性质   总被引:14,自引:0,他引:14  
三草芽孢杆菌(Bacillus subtilis)BM9602产生的中性内切β-甘露聚糖酶(endo-β-1,4-D-mannan mannanohydrolaes,EC,3.2.1.78)经硫酸铵分级沉淀、DEAE-纤维素(DE22)离子交换柱层析,得到电泳纯的样品,提纯了45.5倍,收率为5.9%。用SDS-PAGE测得该酶的分子量为35kD。用PAGEIEF测得其等电点pⅠ为4.5。酶反应的  相似文献   

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鸡减蛋综合征病毒(EggDropSyndromeVirus,EDSV)巯基内肽酶的基因序列分析曾力宇1金奇1朱雷1章金钢2殷震2侯云德1关键词鸡减蛋综合征病毒(EDSV),巯基内肽酶(Thiol-endopeptidase),核苷酸序列分析EDS病毒...  相似文献   

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矿区废弃地的生态恢复研究   总被引:25,自引:3,他引:22  
矿区废弃地的生态恢复研究李玉臣,吉日格拉(赤峰市草原站,024000)(内蒙古草原站)THEECoLOGLCALRESTORAIONSTUDYONMININGDERELICTLANDLiYuchenJirigela(Thegrasslandstati...  相似文献   

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A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.  相似文献   

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We compared the cardiovascular effects evoked in conscious dogs by 1) submaximal exercise; 2) infusion of dobutamine (40 micrograms X kg-1 X min-1); and 3) infusion of a combination of atropine (0.15 mg/kg), norepinephrine (0.19 micrograms X kg-1 X min-1), and epinephrine (0.05 micrograms X kg-1 X min-1). Myocardial O2 demand, as estimated by the double product (heart rate X systolic blood pressure), was similar during all three interventions. Cardiac output and heart rate increased significantly (P less than 0.05) during each of the three interventions. Arteriovenous O2 difference and total body O2 consumption, however, increased only during submaximal exercise. Although myocardial blood flow increased similarly during each of the three interventions, blood flow to skeletal muscle and the tongue increased only during exercise. Exercise and the combined infusion of atropine, norepinephrine, and epinephrine produced similar increases in blood flow to the diaphragm and similar decreases in blood flow to the stomach. These changes in blood flow were associated with appropriate changes in vascular resistance. Additionally, blood flow to the brain, kidney, adrenal glands, liver, and intestine did not change during any of the three interventions. Thus, in dogs, submaximal exercise, infusion of dobutamine, and infusion of a combination of atropine, norepinephrine, and epinephrine to evoke a given level of estimated myocardial O2 consumption produce similar increases in cardiac output, heart rate, and myocardial blood flow. In contrast, the changes in total body O2 consumption, arteriovenous O2 difference, regional blood flow, and regional vascular resistance that occur during each of these three interventions are different.  相似文献   

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Indians, Markets, and Rainforests: Theory, Methods, and Analysis. Ricardo A. Godoy. New York: Columbia University Press, 2001. 274 pp.  相似文献   

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2-Dimethylaminomethylene-1-benzosuberone 1 was coupled with diazotized aniline derivatives to afford a series of the hitherto unreported 2-arylazo-1-benzosuberones 3ai. The tautomeric structure and the effect of substituents on the tautomeric form (s) of the products 3ai were discussed. Similar coupling of the enaminone 1 with diazonium salts of heterocyclic amines gave the respective fused azolotriazino-benzosuberones. Some of the newly synthesized compounds showed potent antimicrobial, anti-HCV, antioxidant, antitumor (as topoisomerase I inhibitors), and antimicrobial activities.  相似文献   

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The Precautionary Principle is in sharp political focus today because (1) the nature of scientific uncertainty is changing and (2) there is increasing pressure to base governmental action on more “rational” schemes, such as cost-benefit analysis and quantitative risk assessment, the former being an embodiment of ‘rational choice theory’ promoted by the Chicago school of law and economics. The Precautionary Principle has been criticized as being both too vague and too arbitrary to form a basis for rational decision making. The assumption underlying this criticism is that any scheme not based on cost-benefit analysis and risk assessment is both irrational and without secure foundation in either science or economics. This paper contests that view and makes explicit the rational tenets of the Precautionary Principle within an analytical framework as rigorous as uncertainties permit, and one that mirrors democratic values embodied in regulatory, compensatory, and common law. Unlike other formulations that reject risk assessment, this paper argues that risk assessment can be used within the formalism of tradeoff analysis—a more appropriate alternative to traditional cost-benefit analysis and one that satisfies the need for well-grounded public policy decision making. This paper will argue that the precautionary approach is the most appropriate basis for policy, even when large uncertainties do not exist, especially where the fairness of the distributions of costs and benefits of hazardous activities and products are a concern. Furthermore, it will offer an approach to making decisions within an analytic framework, based on equity and justice, to replace the economic paradigm of utilitarian cost-benefit analysis.  相似文献   

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